| public static Write ( object element ) : void | ||
| element | object | |
| return | void | |
public void Linq004()
{
//Get a list of customers indicating which month of the year they became clients(take for the month and year of the first order)
var customers = dataSource.Customers.Select(c => new
{
Customer = c.CompanyName,
Date = c.Orders.Any() ?
c.Orders.DefaultIfEmpty()
.OrderBy(o => o.OrderDate)
.FirstOrDefault().OrderDate : // it can be replaced with ?. but i using 2015 VS without C#6
new DateTime()
});
foreach (var c in customers)
{
ObjectDumper.Write(c.Customer + ": " + c.Date.ToShortDateString());
}
}
public void LinqA102()
{
var perMonth = dataSource.Customers
.SelectMany(o => o.Orders.Select(y => y.OrderDate))
.GroupBy(m => m.Year)
.Select(s => new
{
s.Key,
ordersCount = s.Count()
})
.OrderBy(m => m.Key);
ObjectDumper.Write("Year : Count of orders");
foreach (var avg in perMonth)
{
ObjectDumper.Write(avg.Key + " : " + avg.ordersCount);
}
}
public void StartingQuery_6_1()
{
IEnumerable <Chapter06to08.BusinessLogic.Chapter06.Unmapped.Book> books = Chapter06to08.BusinessLogic.Chapter06.Unmapped.Book.GetBooks();
IEnumerable <Chapter06to08.BusinessLogic.Chapter06.Unmapped.Subject> subjects = Chapter06to08.BusinessLogic.Chapter06.Unmapped.Subject.GetSubjects();
var query = from subject in subjects
join book in books on subject.SubjectId equals book.SubjectId
//where book.Price < 30
orderby subject.Description, book.Title
select new
{
subject.Description,
book.Title,
book.Price
};
ObjectDumper.Write(query, 1);
}
public void Linq009()
{
var _outcome = dataSource.Customers
.GroupBy(_fieldOne => _fieldOne.City)
.Select(_fieldOne => new
{
_city = _fieldOne.Key,
_intensive = _fieldOne.Average(_fieldTwo => _fieldTwo.Orders.Length),
_averageSalary = _fieldOne.Average(_fieldTwo => _fieldTwo.Orders.Sum(_salary => _salary.Total))
});
foreach (var _fieldOne in _outcome)
{
ObjectDumper.Write(" City " + _fieldOne._city + "; Intensive " + _fieldOne._intensive + "; Salary " + _fieldOne._averageSalary);
//ObjectDumper.Write(" Intensive " + _fieldOne._intensive);
//ObjectDumper.Write(" Salary " + _fieldOne._averageSalary);
}
}
//Укажите всех клиентов, у которых указан нецифровой почтовый код или не заполнен регион или в телефоне не указан код оператора
public void Linq8()
{
Regex regexPostalCode = new Regex(@"\D{2}");
Regex regexPhone = new Regex(@"[()]");
var customer =
from c in dataSource.Customers
where c.PostalCode != null
where c.Region == null
select c;
foreach (var item in customer)
{
if (regexPostalCode.IsMatch(item.PostalCode) && !regexPhone.IsMatch(item.Phone))
{
ObjectDumper.Write(item);
}
}
}
public void LinqA04()
{
var customers =
from cust in this.dataSource.Customers
where cust.Orders.Any()
select new
{
cust.CompanyName,
Year = cust.Orders.ElementAt(0).OrderDate.Year,
Month = cust.Orders.ElementAt(0).OrderDate.Month
};
ObjectDumper.Write($"Select first order of customer");
foreach (var customer in customers)
{
ObjectDumper.Write(customer);
}
}
public void Linq14()
{
var clients =
from c in dataSource.Customers
orderby c.City
group c by c.City into g
select new
{
City = g.Key,
AverageSum = g.Sum(gc => gc.Orders.Sum(o => o.Total)) / g.Sum(gc => gc.Orders.Count()),
AverageIntensity = g.Sum(gc => gc.Orders.Count()) / (double)g.Count()
};
foreach (var c in clients)
{
ObjectDumper.Write(c);
}
}
public void Linq8()
{
var products =
from p in dataSource.Products
let range = (
p.UnitPrice < 10 ? "cheap" :
p.UnitPrice >= 10 && p.UnitPrice < 20 ? "middle" :
p.UnitPrice >= 20 ? "expensive" :
"unknown_category"
)
orderby range
select new { p.Category, p.UnitPrice, range };
foreach (var p in products)
{
ObjectDumper.Write(p);
}
}
// Ordering Operators
// This sample uses orderby to sort a list of products by units in stock
// from highest to lowest
public void Linq33()
{
List <Products.Product> products = Products.GetProductList();
#region Make Sure to try yourself before looking at the code
// Slightly modified used "Take(10)" to make it compare the results
var sortedProducts =
(from prod in products
orderby prod.UnitsInStock descending
select prod).Take(10);
// Could apply take to "sortedProducts"
// ObjectDumper.Write(sortedProducts.Take(10));
ObjectDumper.Write(sortedProducts);
#endregion
}
public void Linq05()
{
var customers = dataSource.Customers
.Select(customer => new
{
CustomerName = customer.CompanyName,
DateOfFirstOrder = customer.Orders.Select(order => (DateTime?)order.OrderDate).Min(),
Turnover = customer.Orders.Sum(order => order.Total),
})
.OrderBy(customer => customer.DateOfFirstOrder)
.ThenByDescending(customer => customer.Turnover)
.ThenBy(customer => customer.CustomerName);
foreach (var customer in customers)
{
ObjectDumper.Write(customer);
}
}
public void Linq9()
{
var resAvg = dataSource.Customers
.GroupBy(c => c.City)
.Select(c => new
{
City = c.Key,
Intensity = c.Average(p => p.Orders.Length),
AverageIncome = c.Average(p => p.Orders.Sum(o => o.Total))
});
foreach (var group in resAvg)
{
ObjectDumper.Write($"City: {group.City}");
ObjectDumper.Write($"\tIntensity: {group.Intensity}");
ObjectDumper.Write($"\tAverage Income: {group.AverageIncome}");
}
}
public void LinqTask4()
{
var customers = this.dataSource.Customers
.Select(c => new
{
c.CompanyName,
FirstOrder = c.Orders
.Select(o => o.OrderDate)
.FirstOrDefault()
.ToString("MM, yyyy")
})
.Where(y => y.FirstOrder != new DateTime(day: 01, month: 01, year: 01).ToString("MM, yyyy"));
foreach (var c in customers)
{
ObjectDumper.Write(c);
}
}
public static void Main()
{
string connectionString = ConfigurationManager.ConnectionStrings["database-connection-2"].ConnectionString;
using (var sqlConnection
= new SqlConnection(connectionString))
{
sqlConnection.Open();
IEnumerable <dynamic> products = sqlConnection
.Query <dynamic>("Select * from Products where Id = @Id",
new { Id = 2 });
foreach (dynamic product in products)
{
ObjectDumper.Write(string.Format("{0}-{1}", product.Id, product.ProductName));
}
}
}
public void DataSetLinqLamda17()
{
var customers = testDS.Tables["Customers"].AsEnumerable();
var orders = testDS.Tables["Orders"].AsEnumerable();
var myOrders =
customers.SelectMany(c => orders, (c, o) => new { c, o })
.Select(@t => new { @t, total = @t.o.Field <decimal>("Total") })
.Where(@t => @[email protected] <string>("CustomerID") == @[email protected] <string>("CustomerID") && @t.total >= 2000.0M)
.Select(@t =>
new {
CustomerID = @[email protected] <string>("CustomerID"),
OrderID = @[email protected] <int>("OrderID"),
@t.total
});
ObjectDumper.Write(myOrders);
}
public void Linq005()
{
var customers = dataSource.Customers.Where(c => c.Orders.Any())
.Select(c => new
{
ClientName = c.CompanyName,
StartDate = c.Orders.Min(o => o.OrderDate),
Total = c.Orders.Sum(o => o.Total)
}).OrderByDescending(c => c.StartDate.Year)
.ThenByDescending(c => c.StartDate.Month)
.ThenByDescending(c => c.Total)
.ThenBy(c => c.ClientName);;
foreach (var c in customers)
{
ObjectDumper.Write(c);
}
}
public void Linq01()
{
IEnumerable <string> GetCustomersWithTotalTurnoverMoreThanX(
int x, IEnumerable <Customer> customers) =>
customers.
Where(customer => customer.Orders.Sum(o => o.Total) > x).
Select(c => c.CompanyName);
var productsWithTotalTurnoverMoreThan10000 =
GetCustomersWithTotalTurnoverMoreThanX(10000, dataSource.Customers);
var productsWithTotalTurnoverMoreThan5000 =
GetCustomersWithTotalTurnoverMoreThanX(5000, dataSource.Customers);
ObjectDumper.Write("Products With Annual Turnover More Than 10000:");
WriteResult(productsWithTotalTurnoverMoreThan10000);
ObjectDumper.Write("Products With Annual Turnover More Than 5000:");
WriteResult(productsWithTotalTurnoverMoreThan5000);
}
//список поставщиков в той же стране и том же городе
public void Linq4()
{
var listSupplierJoin =
from p in dataSource.Customers
join s in dataSource.Suppliers on p.Country equals s.Country
select new { CompanyName = p.CompanyName, CountryCompany = p.Country, SupplierName = s.SupplierName, CountrySupplier = s.Country };
var listSupplier =
from c in dataSource.Customers
from s in dataSource.Suppliers
where c.Country == s.Country
select new { CompanyName = c.CompanyName, CountryCompany = c.Country, SupplierName = s.SupplierName, CountrySupplier = s.Country };
foreach (var item in listSupplier)
{
ObjectDumper.Write(item);
}
}
public void LinqA08()
{
decimal cheapThreshold = 20;
decimal expensiveThreshold = 40;
var products =
from prod in this.dataSource.Products
group prod by(
prod.UnitPrice <cheapThreshold? "Cheap" :
prod.UnitPrice> expensiveThreshold? "Expensive" : "Middle price"
) into priceGroup
select new { priceGroup.Key, priceGroup };
foreach (var prod in products)
{
ObjectDumper.Write(prod, 2);
}
}
public void Linq008_Sorting()
{
var products = dataSource.Products.Select(p => new
{
p.ProductID,
p.ProductName,
PriceCategory = p.UnitPrice <= 10
? "Cheap"
: (p.UnitPrice <= 20
? "Medium"
: "Expensive")
});
foreach (var product in products)
{
ObjectDumper.Write(product);
}
}
public void DLinq41()
{
var categories =
from p in db.Products
group p by p.Category.CategoryID
into g
orderby g.Key
select new
{
g.Key,
MostExpensiveProducts =
from p2 in g
where p2.UnitPrice == g.Max(p3 => p3.UnitPrice)
select p2
};
ObjectDumper.Write(categories, 1);
}
public void Linq69A()
{
List <Products.Product> products = Products.GetProductList();
#region Linq with Lambda - Make Sure to try yourself before looking at the code
var productGroups = products
.GroupBy(prod => prod.Category)
.Where(prodGroup => prodGroup.Any(p => p.UnitsInStock == 0))
.Select(prodGroup => new { Category = prodGroup.Key, Products = prodGroup });
Console.WriteLine();
Console.WriteLine("***********************************");
Console.Write("Linq with Lambda.");
ObjectDumper.Write(productGroups.Take(1), 1);
#endregion
}
public void LinqTask7()
{
var products = this.dataSource.Products
.GroupBy(p => p.Category)
.Select(c => new
{
Category = c.Key,
Stocks = c.GroupBy(s => s.UnitsInStock == 0 ? "Sold" : "In stock")
.Select(e => new
{
Left = e.Key,
Prices = e
.Select(pr => new { Name = pr.ProductName, Price = pr.UnitPrice }).OrderBy(pr => pr.Price)
})
});
ObjectDumper.Write(products, 2);
}
public void FilteringUnmappedClrMethods_6_11a()
{
Console.WriteLine("This example will intentionally fail because it uses CLR methods improperly.");
using (DataContext dataContext = new DataContext(ConfigurationManager.ConnectionStrings["SqlConStr"].ConnectionString))
{
dataContext.Log = Console.Out;
var books = dataContext.GetTable <Book>();
var query =
from book in books
where book.PublicationDate >= DateTime.Parse("1/1/2007")
select book.PublicationDate.ToString("MM/dd/yyyy");
ObjectDumper.Write(query);
}
}
public void Linq004()
{
var customers = dataSource.Customers;
var customersResult = from customer in customers
where customer.Orders.Count() > 0
select new
{
customer.CompanyName,
customer.Orders.Min(order => order.OrderDate).Month,
customer.Orders.Min(order => order.OrderDate).Year
};
foreach (var customer in customersResult)
{
ObjectDumper.Write(customer);
}
}
public void LinqA8()
{
int Cheap = 20;
int Expensive = 40;
var products = dataSource.Products
.OrderBy(p => p.UnitPrice)
.GroupBy(p => p.UnitPrice < Cheap ? "Cheap" : p.UnitPrice < Expensive ? "Average" : "Expensive")
.Select(x => new {
Price_Category = x.Key,
Product = x.Select(y => new { y.ProductName, y.UnitPrice })
});
foreach (var category in products)
{
ObjectDumper.Write(category, 2);
}
}
public static void Main()
{
string connectionString = ConfigurationManager.ConnectionStrings["database-connection-2"].ConnectionString;
using (var sqlConnection = new SqlConnection(connectionString))
{
sqlConnection.Open();
var db = NorthwindDatabase.Init(sqlConnection, commandTimeout: 2);
var result = db.Suppliers.All();
foreach (var supplier in result)
{
ObjectDumper.Write(supplier);
}
}
}
public void Aggregates_6_14()
{
using (DataContext dataContext = new DataContext(ConfigurationManager.ConnectionStrings["SqlConStr"].ConnectionString))
{
dataContext.Log = Console.Out;
Table <Book> books = dataContext.GetTable <Book>();
var query = from book in books
group book by book.SubjectId into groupedBooks
select new
{
groupedBooks.Key,
BookCount = groupedBooks.Count()
};
ObjectDumper.Write(query, 1);
}
}
public void Linq23()
{
List <Customer> customers = GetCustomerList();
var waOrders =
from cust in customers
from order in cust.Orders
where cust.Region == "WA"
select new { cust.CustomerID, order.OrderID, order.OrderDate };
var allButFirst2Orders = waOrders.Skip(2);
Console.WriteLine("All but first 2 orders in WA:");
foreach (var order in allButFirst2Orders)
{
ObjectDumper.Write(order);
}
}
public void Linq12()
{
int cheap = 25;
int average = 50;
var groups = from p in this.dataSource.Products
group p by p.UnitPrice < cheap ? "Cheap" :
p.UnitPrice < average ? "Average price" : "Expensive";
foreach (var g in groups)
{
ObjectDumper.Write(g.Key);
foreach (var p in g)
{
ObjectDumper.Write(p);
}
}
}
public void Linq001()
{
decimal x = 1500;
var customersList = dataSource.Customers
.Where(c => c.Orders.Sum(o => o.Total) > x)
.Select(c => new
{
CustomerId = c.CustomerID,
TotalSum = c.Orders.Sum(o => o.Total)
});
ObjectDumper.Write($"Greater than {x}");
foreach (var customer in customersList)
{
ObjectDumper.Write($"CustomerId = {customer.CustomerId} TotalSum = {customer.TotalSum}\n");
}
}
/// <summary>
/// Writes the specified element.
/// </summary>
/// <param name="prefix">The prefix to print.</param>
/// <param name="element">The element to dump.</param>
/// <param name="depth">The iteration level.</param>
/// <param name="maxcount">The maximum count of dumps.</param>
/// <param name="log">The output logger.</param>
public static void Write(string prefix, object element, int depth, int maxcount, TextWriter log)
{
ObjectDumper dumper = new ObjectDumper(depth, maxcount);
dumper.writer = log;
// string prefix = null;
if (element != null)
{
dumper.Write("[" + element.GetType().Name + "]" + log.NewLine);
//prefix = "[" + element.GetType().Name + "]";
}
dumper.WriteObject(prefix, element);
}